The invention relates to an apparatus for tapping current from a busbar by means of at least one roller which is arranged, for example, on a trolley.
Normally, current is tapped from busbars using, for example, apparatuses which move in respect to the busbar. These include, in particular, trolleys which are guided along rails, on which the busbars are normally also located. Trolleys are known and are commercially available in widely differing forms and configurations. The trolleys which are referred to in the present exemplary embodiment relate primarily to the transportation of workpieces, material or the like between processing stations in which processing activities are carried out on the workpiece. Such systems are nowadays used, for example, in the electronics industry, in order to fit components to printed circuits or the like. However, it is only by way of example and, according to the invention, apparatuses for tapping current from a busbar may be used in many industrial fields.
One example, in which an apparatus according to the invention for tapping current from a busbar is described, is disclosed in EP-A-0 728 647. The claim there covers the provision of a roller which is composed of electrically conductive material and rolls on the busbar being provided for tapping current.
In practice, it has been found to be disadvantageous that short voltage interruptions occur per busbar when tapping current using a roller, due to expansion joints, dirt or offsets, which then lead to malfunctions, for example on electronically controlled trolleys.
In order to ensure correct operation of electronic components, no voltage interruption may occur below, for example, 5 V (TTL signals) or 12 V (CMOS) etc.